Sheet feeding mechanism for printing presses



July 9, 1940.

W. K.- ECKHARD SHEET FEEDING MECHANISM FOR PRINTING PRESSES Filed Oct. 11, 1939 3 Sheets-Sheet 1 ATTORNEYS July 9, 1940. v w. K. ECKHARD 2,207,508

SHEET FEEDING MECHANISM FOR PRINTING PRESSES Filed Oct. 11, 1939 s Sheets-Sheet 2 ATTORNEY July 9, 1940. w. K. ECKHARD SHEET FEEDING MECHANISM FOR PRINTING PRESSES Filed Oct. 11, 1959 5 Sheets-Sheet 5 INVENTOR ATTORNEYS Patented July 9, 1940 UNITED STATES PATENT OFFICE SHEET FEEDING. IIEOHANISM FOR PRINTING PBESSES Application October 11, 1939, Serial No. 298,999

Claims.

My invention is directed to improvements in so called lap or streamline sheet feeders in which the sheets are fed in lapped relation.

My invention is more particularly directed to 5 feeders of the above type which are adapted to feed in proper register lapped sheets in runs of varying lengths, within predetermined limits.

The object of my invention is to increase production and to obtain improved quality in register of sheets of different length by providing a sheet feeder and a sheet slow-down device for forwarding varying length sheets in lapped relation to a front sheet register guide; means being employed for adjusting both the speed of travel of both the sheet feeder and the sheet slow-down device.

A practical embodiment of my invention is represented in the accompanying drawings, in which Fig. 1 represents a diagrammatic view showing the relative positions of sheets of a maximum length when the leading sheet is in a selected position on the impression cylinder;

Fig. 2 represents a similar view when the leading sheet is in a second position;

Fig. 3 represents a similar view when the leading sheet is in a third position;

Fig. 4 represents a similar view showing the relative positions of sheets of a minimum length when the leading sheet is in a selected position on the impression cylinder;

Fig. 5 represents a similar view when the leading sheet is in a second position;

Fig. 6 represents a similar view when the leading sheet is in a third position;

5 Fig. '7 representsa detail side view partly in section of my improved sheet feeder with the parts in the positions they assume when the maximum length sheets occupy the position shown in Fig. 1;

Fig. 8 represents a similar view with the parts in the positions they assume when the maximum length sheets occupy the positions shown in Fig. 2;

Fig. 9 represents a detail view with the parts in the positions they assume when the sheets occupy the positions shown in Fig. 3; and

Fig. 10 represents the adjusted position on the crank disc of the cam connecting rod for controlling the speed of the sheet slow-down device when used in connection with the minimum length sheets.

The front sheet register guide I is mounted on the rock shaft 2 in position to be swung by the usual means, not shown herein, into and out of position to engage the advance edges of successive sheets as they are fed in lapped relation over the fixed sheet support 3 by the sheet feeder 4, which feeder in the present instance is shown as an endless tape carrier. This endless tape car rier may be driven at the desired speed accord- 5 ing to the length of sheets being fed, by a change speed drive of well known or approved form, through a belt 5 which passes at one end around a pulley 6 on the endless carrier shaft 1 and at its other end around a pulley 8 on the variable 10 speed shaft 9 of the change speed device. This .shaft 9 may be driven from the shaft H) of the change speed device through the usual belt II and divided pulleys l2 and I3. The usual hand wheel l4 may be provided for manually adjust- 1.: ing the effective diameters of the divided pulleys l2 and I3 to vary the speed of the shaft 9, belt 5 and endless tape carrier 4 according to the length of sheets to be fed. The shaft ill of the change speed device may be driven at a constant speed from the rotary crank shaft l5 through the belt l6 and pulleys l1 and I1.

Means are provided for slowing down the fedin sheets to a greater or lesser extent according to their length so that the longer or shorter sheets, as the case may be, will be brought to a substantial stop as their advance edges reach the front register guide I. This adjustable slowdown device is herein shown as comprising the following elements: the spring pressed slow-down o hooks l8 (one only of which is shown) are hinged as usual to a carriage i9 at each side of the feeder,.which carriage is reciprocated just below the fixed sheet support 3. These slowdown hooks l8 are yieldingly held at the limit 35 of their upward movement in the path ofthe advancing lapped sheets by a spring 20 on each carriage IS. The usual hook swinging roller 2| travels around the track 22 as the carriage is. reciprocated, to bring the hooks into and out of the path of the advancing sheets as the carriage moves forward and backward respectively.

A rod 23 connects the carriage l9 to one arm 24 of a rock lever carried by the rock shaft 25; the other arm 26 of which lever carries a roller 21' which is operated by the inclined surface of a cam 28 slidably mounted on. a fixed bar 29.

This cam 28 is connected to one end of a rod 30, the other end of which rod is adjustably connected to a crank disc 3| carried on the rotary 5o shaft l5. This connection of the rod 30 with the crank disc 3| may be adjusted toward and away from the shaft l5 to vary the throw of the cam 28 and thereby the speed of the slow-down hooks according to the length of sheets being fed; it being understood that-the throw of the connecting rod III is decreased for a shorter sheet and increased fora longer sheet. The crank disc 3| rotates once for each sheet being fed. In Figs. 7 and 8 the connection between the rod and the crank disc 3| is shown as adjusted outwardly for the maximum length sheets while in Fig. 10 the connection is shown as adjusted inwardly for a minimum length sheet.

The rotary impression cylinder is denoted by 32 and its sheet -grippers by 33. The rotary sheet transfer carrier is denoted by 34 and its grippers by 85. These gripper 35 are arranged to take the head of theregistered fed-in sheet from the front register guide I and to present it to the impressioncylinder grippers 33.

The longer sheets illustrated in Figs. 1, 2 and 3 are denoted by A, B, C, D and the corresponding shorter sheets illustrated in Figs. 4, 5 and 6 are denoted by A, B, C, D.

It will be noted that when the parts are in the position shown in Fig. l or 4 the longer sheet A or the shorter sheet A, as the case may be, is engaged by the impression cylinder grippers I3 and the tail of the sheet is just clearing the head of sheet B or B which is just contacting the slowdown hooks I8. Sheets C or C" and D or D are being conveyed in a lapped relation by the feeder to the press. In Fig. 2 or 5 the sheet A or A advancing at cylinder speed shows more clearness between the sheets A or A and B or B which has just reached the front register guides I. The overlap between the sheets B or B and C or C is increased due to retarding speed of sheet B or B' in the slow-down hooks I8. Sheets C or C and D or D run at uniform speed with overlap remaining the same. In Fig. 3 or 6 the sheet A or A is still advancingat cylinder speed. The grippers 35 on the rotary transfer carrier 34 are just taking the sheet B or B with the front sheet guides I just starting to move to the position shown in Fig. 1 or 4. The overlap between sheets B or B and C or C has increased while sheet B or B remain at the front register guide I during the side guiding period. The sheets C or C and D or D run at uniform speed with lap remaining the same.

From the above description it will be seen that by regulating the speed of the feeder and the speed of the slow-down device proportional to the length of the sheets being fed-in to the press, sheet lengths withinthe capacity of the press may be delivered to the front register guides with positive control and in proper timed relation so as not to interfere with side guiding or other functioning mechanism and with no interference between the tail of a preceding sheet with the advance edge of the next succeeding. sheet.

It is evident that this feeding mechanism can be applied to both under-fed and over-fed machines with equal advantage.

It is evident that various changes may be resorted to in the construction, form and arrangement of the several parts without departing from the spirit and'scope of my invention, and hence I do not intend to be limited to the particular embodiment herein shown and described, but what I claim is:

1. In a sheet fed rotary printing press, a front sheet register guide, a device for forwarding lapped sheets of diflerent lengths thereto, a sheet slow-down device adjacent the front sheet register guide, and manually controlled means for varying the speed of travel of both the sheet forwarding device and the sheet slow-down deice accordingto the length of the sheets being 2. In a sheet fed rotary printing press, a front sheet register guide, a traveling endless carrier for forwarding lapped sheets of different lengths thereto, a sheet slow-down device adjacent the front sheet register guide, and manually controlled means for varying the speed of travel of both the endless carrier and the sheet slow-down device according to the length of the sheets being 3. In a sheet fed rotary printing press, a front sheet register guide, a traveling endless carrier for forwarding lapped sheets of different lengths thereto, a sheet slow-down device adjacent the front sheet register guide, and manually controlled means for varying the speed of travel of both the endless carrier and the sheet slow-down device according to the length of the sheets being fed, said means including a change speed device operatively connected to the endless carrier.

4. In a sheet fed rotary printing press, a front sheet register guide, a traveling endless carrier for forwarding lapped sheets of different lengths thereto, a sheet slow-down device, and manually controlled means for varying the speed of travel of both the endless carrier and the sheet slowdown device according to the length of the sheets being fed, said means including a change speed device operatively connected to the endless carrier and a rotary crank of adjustable throw for operating the slow-down device.

5. In a sheet fed rotary printing press, a front sheet register guide, a traveling endless carrier for forwarding lapped sheets of different lengths thereto, a sheet slow-down device comprising a reciprocating carriage, sheet engaging hooks carried thereby, a rock lever connected to the carriage, a cam for operating the rock lever and a rotary crank for operating the cam, and manually controlled means for varying the speed of travel of both the endless carrier and the sheet slow-down device according to the length of the sheets being fed, said means including a change speed device operatively connected to the endless carrier and means for varying the throw of the rotary crank.-

W'ILLIAM K. ECKHARD. 

